KEY NUMBERS · RUBY, PER CARAT
$1–$50
glass-filled material
$2k–$10k
fine heated ruby
$1.2M
record, Sunrise Ruby (2015)
Ruby price per carat runs from a few dollars for glass-filled material to over $1 million for exceptional unheated Burmese stones. Most fine heated rubies trade between about $2,000 and $10,000 per carat.
Four variables decide where a stone sits: color, treatment, size and origin, in that order.
TL;DR
Quotes without color grade, treatment status and size are meaningless.
Price per carat rises with size: 3 carats costs far more per carat than 1 carat of the same quality.
Unheated status is a multiple at the top of the market, not a percentage.
A vivid, transparent ruby priced like a commercial stone is almost always glass-filled or synthetic.
Ruby Price Per Carat by Quality Tier
Indicative ranges for natural rubies of about 1 to 2 carats, drawn from dealer estimates and auction results. Use them to calibrate a quote, not as a price list.
Tier | Typical description | Indicative price per carat |
|---|---|---|
Composite (lead-glass filled) | Looks transparent and vivid, heavily fractured underneath | Roughly $1 to $50 |
Commercial | Heated, included, dark or pinkish, often from mixed origins | Roughly $50 to $500 |
Good | Attractive red, heated, some visible inclusions | Roughly $500 to $2,000 |
Fine | Strong red, heated, eye-clean or close | Roughly $2,000 to $10,000 |
Very fine, unheated | Vivid red, no indications of heating, top-lab report | Roughly $10,000 to $50,000+ |
Exceptional | Large, unheated, vivid, Burma or top Mozambique | $100,000 to $1,000,000+ at auction |
Our take: the gap people misread is between commercial and fine. Both are sold as "ruby", but a fine ruby is a different product, not an expensive version of a cheap one.
Most rough never becomes a fine stone. The price per carat of the finished gem reflects that attrition.
How Much Is a 1-Carat Ruby Worth?
Usually a few hundred dollars to about $10,000. A heated stone with good red sits in the low thousands.
An unheated 1-carat stone with vivid color and a GRS, Gübelin or SSEF report can pass $10,000. Glass-filled 1-carat "rubies" sell for tens of dollars.
Why price per carat jumps with size
Clean fine rough above 2 or 3 carats is far rarer than small rough. Prices step up at 1, 2, 3 and 5 carats; above 5 carats, fine unheated stones are priced one by one, usually at auction.
Size | Effect on price per carat (same quality) |
|---|---|
Under 1 ct | Baseline |
1 to 2 ct | Noticeably higher |
2 to 3 ct | Higher again; fine material becomes scarce |
3 to 5 ct | A step change for fine and unheated stones |
5 ct and up | Individually priced, often by auction |
Heated vs. Unheated Ruby Price
Most rubies are heated, and buyers pay a clear premium for "no indications of heating." Dealers commonly cite 2x to 5x for comparable unheated stones, rising with size.
Heated stones are split again by residue: minor, moderate or significant. Each step down costs value.
For the full mechanics of heating and how labs detect it, read Heated vs. Unheated Sapphire; the logic applies equally to ruby.
Price lists age fast. Auction results don't lie.
Every Tuesday, the Carat Brief Index tracks public pricing signals for ruby and seven other reference stones: auctions, producer results, and lab language.
Ruby Price Per Carat by Origin
Origin only adds value when a top lab states it. With that caveat, the hierarchy for comparable stones is consistent.
Origin | Relative price position | Notes |
|---|---|---|
Burma (Myanmar) | Highest | The historic benchmark, especially unheated Mogok material. Sanctions restrict trade in some markets. |
Mozambique | High for top stones | The volume leader for fine ruby. The best stones compete with Burma; the record Estrela de Fura is Mozambican. |
Vietnam, Afghanistan, Tajikistan | Mid to high | Marble-hosted, can show Burma-like color. |
Madagascar, Tanzania, Kenya | Mid | Wide quality range. |
Thailand / Cambodia | Lower for same appearance | Iron-rich, darker, weak fluorescence. |
What Gemfields auctions say about wholesale prices
Gemfields sells rough from Montepuez, Mozambique, at auction and publishes the results. It is the best public read on wholesale ruby demand.
2026 auction | Revenue | Average per carat |
|---|---|---|
February, mixed quality | ~$53M | $279 |
June, Trade Select (lower grades) | $23.1M | $66.30 |
October, mixed quality | ~$52M | $564.54 |
These are rough-ruby averages across many grades, so compare them with each other, not with cut-stone prices. October was a smaller sale with more top-tier stones. We cover every Gemfields sale in the weekly edition.
Ruby vs. Diamond Price Per Carat
At commercial quality, diamonds cost more. At the very top, ruby wins. The 25.59-carat Sunrise Ruby sold for about $1.2 million per carat in 2015, a level only exceptional diamonds reach. See The Most Expensive Rubies Ever Sold.
How to Read a Ruby Price Quote
Check the treatment line first. "No indications of heating," "heated," or "heated with residues (minor / moderate / significant)" changes the price more than anything else on the page.
Check the lab. GIA, GRS, Gübelin, SSEF and AGL reports are accepted at auction. In-house certificates are marketing.
Compare inside the same size band. A 2.9-carat and a 3.1-carat stone can sit in different price brackets.
Discount unproven origin to zero. "Burmese" on a listing without a report adds nothing.
Be suspicious of bargains. If the price per carat looks like commercial grade but the stone looks fine, it is probably glass-filled. See Glass-Filled Ruby.
FAQ
How much is a ruby worth per carat? From a few dollars for glass-filled material to over $1 million for exceptional unheated Burmese stones. Most fine heated rubies trade roughly between $2,000 and $10,000 per carat.
How much is a 1-carat ruby worth? Typically a few hundred dollars to about $10,000. Unheated 1-carat stones with vivid color and a top-lab report can go higher.
Why are Burmese rubies so expensive? Low-iron Mogok rubies fluoresce strongly and show the most sought-after red, supply is limited and politically constrained, and the origin carries centuries of collector prestige.
Are rubies a good investment? Fine unheated rubies with top-lab reports have historically held value well, but the market is illiquid, dealer spreads are wide, and there is no official price index. Buy for the stone, not as a substitute for a financial asset.
Is ruby more expensive than diamond? At the top of the market, yes per carat. At commercial quality, diamonds usually cost more.
Ruby prices move. We track them weekly.
Gemfields auctions, record sales, and the treatment language that changes a price by a multiple. One email, every Tuesday.
Useful Sources
GIA, Ruby Quality Factors: how color, clarity, cut and carat affect value.
Gemfields: official Montepuez ruby auction results.
Lotus Gemology, Auction Records: ruby, sapphire and spinel results.
Carat Brief, What Is Ruby?: color, origin and treatment fundamentals.